<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<p id="p"></p>
<a href="03_history2.html"> 去第二个页面</a>
<button id="go1"> 去指定的页面</button>
<script>
var p = document.getElementById("p");
p.innerHTML = history.length;

go1.onclick = function (){
    history.go(2)
}
</script>
</body>
</html>